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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    <a name="line.17"></a>
<FONT color="green">018</FONT>    package org.apache.commons.net.tftp;<a name="line.18"></a>
<FONT color="green">019</FONT>    <a name="line.19"></a>
<FONT color="green">020</FONT>    import java.net.DatagramPacket;<a name="line.20"></a>
<FONT color="green">021</FONT>    import java.net.InetAddress;<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>    /***<a name="line.23"></a>
<FONT color="green">024</FONT>     * A final class derived from TFTPPacket definiing the TFTP Acknowledgement<a name="line.24"></a>
<FONT color="green">025</FONT>     * packet type.<a name="line.25"></a>
<FONT color="green">026</FONT>     * &lt;p&gt;<a name="line.26"></a>
<FONT color="green">027</FONT>     * Details regarding the TFTP protocol and the format of TFTP packets can<a name="line.27"></a>
<FONT color="green">028</FONT>     * be found in RFC 783.  But the point of these classes is to keep you<a name="line.28"></a>
<FONT color="green">029</FONT>     * from having to worry about the internals.  Additionally, only very<a name="line.29"></a>
<FONT color="green">030</FONT>     * few people should have to care about any of the TFTPPacket classes<a name="line.30"></a>
<FONT color="green">031</FONT>     * or derived classes.  Almost all users should only be concerned with the<a name="line.31"></a>
<FONT color="green">032</FONT>     * {@link org.apache.commons.net.tftp.TFTPClient} class<a name="line.32"></a>
<FONT color="green">033</FONT>     * {@link org.apache.commons.net.tftp.TFTPClient#receiveFile receiveFile()}<a name="line.33"></a>
<FONT color="green">034</FONT>     * and<a name="line.34"></a>
<FONT color="green">035</FONT>     * {@link org.apache.commons.net.tftp.TFTPClient#sendFile sendFile()}<a name="line.35"></a>
<FONT color="green">036</FONT>     * methods.<a name="line.36"></a>
<FONT color="green">037</FONT>     * &lt;p&gt;<a name="line.37"></a>
<FONT color="green">038</FONT>     * &lt;p&gt;<a name="line.38"></a>
<FONT color="green">039</FONT>     * @author Daniel F. Savarese<a name="line.39"></a>
<FONT color="green">040</FONT>     * @see TFTPPacket<a name="line.40"></a>
<FONT color="green">041</FONT>     * @see TFTPPacketException<a name="line.41"></a>
<FONT color="green">042</FONT>     * @see TFTP<a name="line.42"></a>
<FONT color="green">043</FONT>     ***/<a name="line.43"></a>
<FONT color="green">044</FONT>    <a name="line.44"></a>
<FONT color="green">045</FONT>    public final class TFTPAckPacket extends TFTPPacket<a name="line.45"></a>
<FONT color="green">046</FONT>    {<a name="line.46"></a>
<FONT color="green">047</FONT>        /*** The block number being acknowledged by the packet. ***/<a name="line.47"></a>
<FONT color="green">048</FONT>        int _blockNumber;<a name="line.48"></a>
<FONT color="green">049</FONT>    <a name="line.49"></a>
<FONT color="green">050</FONT>        /***<a name="line.50"></a>
<FONT color="green">051</FONT>         * Creates an acknowledgment packet to be sent to a host at a given port<a name="line.51"></a>
<FONT color="green">052</FONT>         * acknowledging receipt of a block.<a name="line.52"></a>
<FONT color="green">053</FONT>         * &lt;p&gt;<a name="line.53"></a>
<FONT color="green">054</FONT>         * @param destination  The host to which the packet is going to be sent.<a name="line.54"></a>
<FONT color="green">055</FONT>         * @param port  The port to which the packet is going to be sent.<a name="line.55"></a>
<FONT color="green">056</FONT>         * @param blockNumber  The block number being acknowledged.<a name="line.56"></a>
<FONT color="green">057</FONT>         ***/<a name="line.57"></a>
<FONT color="green">058</FONT>        public TFTPAckPacket(InetAddress destination, int port, int blockNumber)<a name="line.58"></a>
<FONT color="green">059</FONT>        {<a name="line.59"></a>
<FONT color="green">060</FONT>            super(TFTPPacket.ACKNOWLEDGEMENT, destination, port);<a name="line.60"></a>
<FONT color="green">061</FONT>            _blockNumber = blockNumber;<a name="line.61"></a>
<FONT color="green">062</FONT>        }<a name="line.62"></a>
<FONT color="green">063</FONT>    <a name="line.63"></a>
<FONT color="green">064</FONT>        /***<a name="line.64"></a>
<FONT color="green">065</FONT>         * Creates an acknowledgement packet based from a received<a name="line.65"></a>
<FONT color="green">066</FONT>         * datagram.  Assumes the datagram is at least length 4, else an<a name="line.66"></a>
<FONT color="green">067</FONT>         * ArrayIndexOutOfBoundsException may be thrown.<a name="line.67"></a>
<FONT color="green">068</FONT>         * &lt;p&gt;<a name="line.68"></a>
<FONT color="green">069</FONT>         * @param datagram  The datagram containing the received acknowledgement.<a name="line.69"></a>
<FONT color="green">070</FONT>         * @throws TFTPPacketException  If the datagram isn't a valid TFTP<a name="line.70"></a>
<FONT color="green">071</FONT>         *         acknowledgement packet.<a name="line.71"></a>
<FONT color="green">072</FONT>         ***/<a name="line.72"></a>
<FONT color="green">073</FONT>        TFTPAckPacket(DatagramPacket datagram) throws TFTPPacketException<a name="line.73"></a>
<FONT color="green">074</FONT>        {<a name="line.74"></a>
<FONT color="green">075</FONT>            super(TFTPPacket.ACKNOWLEDGEMENT, datagram.getAddress(),<a name="line.75"></a>
<FONT color="green">076</FONT>                  datagram.getPort());<a name="line.76"></a>
<FONT color="green">077</FONT>            byte[] data;<a name="line.77"></a>
<FONT color="green">078</FONT>    <a name="line.78"></a>
<FONT color="green">079</FONT>            data = datagram.getData();<a name="line.79"></a>
<FONT color="green">080</FONT>    <a name="line.80"></a>
<FONT color="green">081</FONT>            if (getType() != data[1])<a name="line.81"></a>
<FONT color="green">082</FONT>                throw new TFTPPacketException("TFTP operator code does not match type.");<a name="line.82"></a>
<FONT color="green">083</FONT>    <a name="line.83"></a>
<FONT color="green">084</FONT>            _blockNumber = (((data[2] &amp; 0xff) &lt;&lt; 8) | (data[3] &amp; 0xff));<a name="line.84"></a>
<FONT color="green">085</FONT>        }<a name="line.85"></a>
<FONT color="green">086</FONT>    <a name="line.86"></a>
<FONT color="green">087</FONT>        /***<a name="line.87"></a>
<FONT color="green">088</FONT>         * This is a method only available within the package for<a name="line.88"></a>
<FONT color="green">089</FONT>         * implementing efficient datagram transport by elminating buffering.<a name="line.89"></a>
<FONT color="green">090</FONT>         * It takes a datagram as an argument, and a byte buffer in which<a name="line.90"></a>
<FONT color="green">091</FONT>         * to store the raw datagram data.  Inside the method, the data<a name="line.91"></a>
<FONT color="green">092</FONT>         * is set as the datagram's data and the datagram returned.<a name="line.92"></a>
<FONT color="green">093</FONT>         * &lt;p&gt;<a name="line.93"></a>
<FONT color="green">094</FONT>         * @param datagram  The datagram to create.<a name="line.94"></a>
<FONT color="green">095</FONT>         * @param data The buffer to store the packet and to use in the datagram.<a name="line.95"></a>
<FONT color="green">096</FONT>         * @return The datagram argument.<a name="line.96"></a>
<FONT color="green">097</FONT>         ***/<a name="line.97"></a>
<FONT color="green">098</FONT>        @Override<a name="line.98"></a>
<FONT color="green">099</FONT>        DatagramPacket _newDatagram(DatagramPacket datagram, byte[] data)<a name="line.99"></a>
<FONT color="green">100</FONT>        {<a name="line.100"></a>
<FONT color="green">101</FONT>            data[0] = 0;<a name="line.101"></a>
<FONT color="green">102</FONT>            data[1] = (byte)_type;<a name="line.102"></a>
<FONT color="green">103</FONT>            data[2] = (byte)((_blockNumber &amp; 0xffff) &gt;&gt; 8);<a name="line.103"></a>
<FONT color="green">104</FONT>            data[3] = (byte)(_blockNumber &amp; 0xff);<a name="line.104"></a>
<FONT color="green">105</FONT>    <a name="line.105"></a>
<FONT color="green">106</FONT>            datagram.setAddress(_address);<a name="line.106"></a>
<FONT color="green">107</FONT>            datagram.setPort(_port);<a name="line.107"></a>
<FONT color="green">108</FONT>            datagram.setData(data);<a name="line.108"></a>
<FONT color="green">109</FONT>            datagram.setLength(4);<a name="line.109"></a>
<FONT color="green">110</FONT>    <a name="line.110"></a>
<FONT color="green">111</FONT>            return datagram;<a name="line.111"></a>
<FONT color="green">112</FONT>        }<a name="line.112"></a>
<FONT color="green">113</FONT>    <a name="line.113"></a>
<FONT color="green">114</FONT>    <a name="line.114"></a>
<FONT color="green">115</FONT>        /***<a name="line.115"></a>
<FONT color="green">116</FONT>         * Creates a UDP datagram containing all the TFTP<a name="line.116"></a>
<FONT color="green">117</FONT>         * acknowledgement packet data in the proper format.<a name="line.117"></a>
<FONT color="green">118</FONT>         * This is a method exposed to the programmer in case he<a name="line.118"></a>
<FONT color="green">119</FONT>         * wants to implement his own TFTP client instead of using<a name="line.119"></a>
<FONT color="green">120</FONT>         * the {@link org.apache.commons.net.tftp.TFTPClient}<a name="line.120"></a>
<FONT color="green">121</FONT>         * class.  Under normal circumstances, you should not have a need to call this<a name="line.121"></a>
<FONT color="green">122</FONT>         * method.<a name="line.122"></a>
<FONT color="green">123</FONT>         * &lt;p&gt;<a name="line.123"></a>
<FONT color="green">124</FONT>         * @return A UDP datagram containing the TFTP acknowledgement packet.<a name="line.124"></a>
<FONT color="green">125</FONT>         ***/<a name="line.125"></a>
<FONT color="green">126</FONT>        @Override<a name="line.126"></a>
<FONT color="green">127</FONT>        public DatagramPacket newDatagram()<a name="line.127"></a>
<FONT color="green">128</FONT>        {<a name="line.128"></a>
<FONT color="green">129</FONT>            byte[] data;<a name="line.129"></a>
<FONT color="green">130</FONT>    <a name="line.130"></a>
<FONT color="green">131</FONT>            data = new byte[4];<a name="line.131"></a>
<FONT color="green">132</FONT>            data[0] = 0;<a name="line.132"></a>
<FONT color="green">133</FONT>            data[1] = (byte)_type;<a name="line.133"></a>
<FONT color="green">134</FONT>            data[2] = (byte)((_blockNumber &amp; 0xffff) &gt;&gt; 8);<a name="line.134"></a>
<FONT color="green">135</FONT>            data[3] = (byte)(_blockNumber &amp; 0xff);<a name="line.135"></a>
<FONT color="green">136</FONT>    <a name="line.136"></a>
<FONT color="green">137</FONT>            return new DatagramPacket(data, data.length, _address, _port);<a name="line.137"></a>
<FONT color="green">138</FONT>        }<a name="line.138"></a>
<FONT color="green">139</FONT>    <a name="line.139"></a>
<FONT color="green">140</FONT>    <a name="line.140"></a>
<FONT color="green">141</FONT>        /***<a name="line.141"></a>
<FONT color="green">142</FONT>         * Returns the block number of the acknowledgement.<a name="line.142"></a>
<FONT color="green">143</FONT>         * &lt;p&gt;<a name="line.143"></a>
<FONT color="green">144</FONT>         * @return The block number of the acknowledgement.<a name="line.144"></a>
<FONT color="green">145</FONT>         ***/<a name="line.145"></a>
<FONT color="green">146</FONT>        public int getBlockNumber()<a name="line.146"></a>
<FONT color="green">147</FONT>        {<a name="line.147"></a>
<FONT color="green">148</FONT>            return _blockNumber;<a name="line.148"></a>
<FONT color="green">149</FONT>        }<a name="line.149"></a>
<FONT color="green">150</FONT>    <a name="line.150"></a>
<FONT color="green">151</FONT>    <a name="line.151"></a>
<FONT color="green">152</FONT>        /*** Sets the block number of the acknowledgement.  ***/<a name="line.152"></a>
<FONT color="green">153</FONT>        public void setBlockNumber(int blockNumber)<a name="line.153"></a>
<FONT color="green">154</FONT>        {<a name="line.154"></a>
<FONT color="green">155</FONT>            _blockNumber = blockNumber;<a name="line.155"></a>
<FONT color="green">156</FONT>        }<a name="line.156"></a>
<FONT color="green">157</FONT>    }<a name="line.157"></a>
<FONT color="green">158</FONT>    <a name="line.158"></a>




























































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